Dye anionic sorption in aqueous solution onto a cellulose surface chemically modified with aminoethanethiol

Use of Cellulosic Materials as Dye Adsorbents — A Prospective Study

“…Considering that the dye molecules used in their studies have negative charges, the increase for dye removed at lower pH values than 6 is explained by favoring attraction electrostatic between dye and this adsorbent medium, cell-R-N + (C 2 H 5 ) 3 SO 3 − , but at pH values higher than 6, a decrease in the removal of dye different from the work described in reference [12] was noted. Due to the possibility of covalent interactions, they described good results at pH 9.…”

“…This study is very important (12 of 23 articles found on the prospection assessed the influence of this parameter in its work) and should always be performed in the adsorption tests because whether the pH will influence the adsorption process depends on the adsorbent and/or dye used. Table 3 shows the reference [12] that evaluated the influence of pH on the reactive red dye adsorption on the surface of the modified cellulose with aminoethanethiol, and it presents the maximum adsorption capacity at pH 2 and pH 9. The authors explained that the maximum adsorption is favored by electrostatic interactions at pH 2 and by the formation of hydrogen bonds and/or covalent interactions with the adsorbent at pH 9.…”

“…In most of the articles investigated in the literature, it was observed that experimental data usually adjust better to the pseudo-second order kinetic model because the adsorption process is dependent on both the concentration of the adsorbate with the strength of the adsorbent [48,52,12,51,61,62,63]. …”

“…It is even more attractive when it makes modifications in its structure in order to improve their existing properties or adding new potentialities to this material [12,[28][29][30].…”

Functionalization of Microcrystalline Cellulose with N,N-dimethyldodecylamine for the Removal of Congo Red Dye from an Aqueous Solution

“…Due to their complex chemical structures, most of them are stable to light and oxidizing agents. Some dyes have been reported to cause allergic dermatitis or skin irritation, and they may be potentially carcinogenic and mutagenic in humans (Sun and Yang 2003;Bhatnagar and Jain 2005;Silva et al 2013). Congo Red dye (CR) has a molecular weight of 696.68 g•mol -1 and has a benzidine-based structure.…”